We were based out in northern Kenya for six weeks, and had about 10 days spare before the RAF came to collect us. Rather than just sit around, our policy is to try and do things that challenge the guys. I used to be afraid of deep water, but when I swam with sharks and tried scuba diving I totally overcame it. I still had a fear of heights, so when the opportunity arose to do some parachuting down in Malindi, I took it.

We were crammed into a very small plane — a Cessna 102. There were four of us in the back, between each other’s legs. When you prepare to jump, you sit with your feet trailing out, being blown in the wind.

I was attached to a static line, which means as you fall away from the plane, a wire pulls the parachute out of your backpack. As I jumped, my arm bounced off the side of the plane and so I fell very badly. I was tumbling and turning, so the line pulled my parachute out, but also tied it up around me, so it didn’t open up.

You’re supposed to count to three — one thousand, two thousand, three thousand — then check your canopy. There was nothing there. In the air, your perception of time radically alters, so I tried it again. I counted to three, looked up, but it was still not there. I remember thinking: “Of all the people I know to be having a malfunction, it would be you, on your third jump, Williams.”

I went into my drills immediately. I tried hard to untangle myself and cut my old chute, but couldn’t. Your reserve chute is on a spring, which fires it out of your backpack, but because the strings were all tied round me, it couldn’t get out. It was only at that point I looked at the ground and went: “Right, I’m dead.” It was that simple.

I’m not in any way an exceptionally brave person, but it’s extraordinary how clear-minded I was. Afterwards it took five or six weeks to work through and realise that everything we do in life, we have a choice. There, for the first time,

I had no choice. I was about to die and there was absolutely nothing I could do.

I know it seems like a cliché to say that my life flashed before my eyes, but that’s exactly what happened.

It felt as if in about two seconds I’d considered everything in my life — and I’m no saint. But it was really reassuring to think: “Actually, I’m happy with the life I’ve led.”

I also remember feeling sorry for my parents and quite lonely. When you’re 3,500ft up, you’re a kilometre from the nearest living thing: you don’t get an option as to your last words.

Then I saw the main electricity power lines that come up the coast from Mombasa to Malindi. With a touch of irony I thought: “I’d better not hit those, I might get electrocuted!” I’d utterly accepted that I was going to die and so was actually very relaxed. I remember thinking how beautiful it all was, with the Indian Ocean on one side, clear blue skies, and the African landscape all laid out in front of me. I thought: “If you’re gonna go, what a way.”

I then fell to Earth. The whole thing took about 40 seconds, and you’re nearing speeds of about 90mph — imagine standing in the road and a 100mph car hitting you. I managed to hit this corrugated iron roof, which gave way. I then bounced off a side wall and ended up face-down on the ground — so no great sudden stop. It was huge luck, and no skill on my part, because it was about the only building on its own in this massive open area of hard-baked earth.

I never lost consciousness. When I looked up, there were 10 or 15 Africans watching me, not saying a word. I remember lying there thinking: “Of all the people that should have died on landing, it’s you, Williams, you lunatic.”

I was a bit woozy and didn’t feel any pain for a couple of minutes — the body is in a degree of shock. I looked across and thought: “Oh God, my arm’s been ripped off!” I was wearing this bright-orange jumpsuit, so it was quite hard to discern that my arm was actually just underneath me. My finger was sticking out at an odd angle, but it was only dislocated, so I just popped it back in.

Probably the worst moment of the whole thing was going: “Right, my feet, my legs… I must be paralysed.” As it turned out, there was only a slight fracture on one of my vertebrae, but my back literally turned black with bruising.

I haven’t jumped since. I would like to, but I know someone would have to kick me out the door. One of the things I find very hard to do is to compute or put a measure to how lucky I was. I should have died that day. What I realised is, it wasn’t my time — but I’ve never stood up and said: “I’m amazing because I fell out of a plane.” I see myself as a sort of spectator to an amazing incident. Yes,

I was the guy at the centre of it, but if I had run into a burning building and saved three babies, then I’d be a hero.

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